Calcaling pegmatite, Mukinbudin, Mukinbudin Shire, Western Australia, Australiai

Regional Level Types
Calcaling pegmatite	Pegmatite
Mukinbudin	- not defined -
Mukinbudin Shire	Shire
Western Australia	State
Australia	Country

Located 27 kilometres east of Mukinbudin on the west side of Quanta Cutting-Weira Road.

Mining activity has created a pit ten to fourteen metres deep, seventy metres long and fifty metres wide, with several mullock piles surrounding it. Mining here was started by Imdex Feldspar Pty Ltd in 1995 till 1997, when the company considered the feldspar reserves had been exhausted. At this time, Robert (Bob) Jones of Rural Prospecting Pty Ltd purchased the lease to work the surface mullock piles for decorative crushed white quartz.
No active mining could be seen from the road when the site was visited in 2011, but may still be under lease.

The deposit lies outside the Murchison terranes of the other sites in the Mukinbudin area. The country rock is highly weathered biotite adamellite heavily foliated along sub-horizontal zones. The pegmatite shows discontinuous quartz core segments in its centre, with graphic granite and quartz fracture fillings forming fingers into the surrounding biotite adamellite, in a highly irregular shape.

Bob Jones is largely responsible for what we know of this pegmatite, as he took an interest in the mineralogy of the deposit. A number of interesting mineral species came to light from his work. It is said some of the finest smokey quartz crystals found in Western Australia came from a pocket in the albite unit along the quarry wall. Associated with the albite is ilmenite, ilmenorutile and euxenite (Y). The ilmenorutile forms bluish-black metallic crystals six to ten centimetres long. Ilmenite is found up to 15 centimetres long as flat bladed crystals, sometimes intergrown with metamict euhedral euxenite (Y) crystals. There are descriptions of specimens found showing black lustrous euxenite (y) forming a row of crystals on an ilmenite plate.
Studies of the euxenite crystals have shown niobium to be paramount at 36.60%,weight, tantalum 15.70% and yttrium at 12%. Bright yellow massive fluorite is relatively common on the mullock piles. Beryl, monazite,molybdenum and magnetite crystals have been found in minor amounts.

Other Regions, Features and Areas containing this locality

References